/**
 * Copyright (C) 2002-2015   The FreeCol Team
 * <p>
 * This file is part of FreeCol.
 * <p>
 * FreeCol is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 * <p>
 * FreeCol is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * <p>
 * You should have received a copy of the GNU General Public License
 * along with FreeCol.  If not, see <http://www.gnu.org/licenses/>.
 */

package net.sf.freecol.common.model;

import java.util.ArrayList;
import java.util.List;
import java.util.logging.Logger;

import javax.xml.stream.XMLStreamException;

import net.sf.freecol.common.io.FreeColXMLReader;
import net.sf.freecol.common.io.FreeColXMLWriter;


/**
 * An object representing the high seas between continents.
 */
public class HighSeas extends UnitLocation
{

    private static final Logger logger = Logger.getLogger( HighSeas.class.getName( ) );

    /** The destinations this HighSeas object connects. */
    private final List< Location > destinations = new ArrayList<>( );


    /**
     * Simple constructor.
     *
     * @param game The enclosing <code>Game</code>.
     */
    public HighSeas( Game game )
    {
        super( game );
    }

    /**
     * Create a new high seas.
     *
     * @param game The enclosing <code>Game</code>.
     * @param id The object identifier.
     */
    public HighSeas( Game game, String id )
    {
        super( game, id );
    }


    /**
     * Get the destinations connected by these seas.
     *
     * @return A list of <code>Location</code>s.
     */
    public final List< Location > getDestinations( )
    {
        return destinations;
    }

    /**
     * Add a single destination to this HighSeas instance.
     *
     * @param destination A destination <code>Location</code>.
     */
    public void addDestination( Location destination )
    {
        if ( destination != null )
        {
            if ( ! destinations.contains( destination ) )
            {
                destinations.add( destination );
            }
            else
            {
                logger.warning( getId( ) + " already included destination "
                                        + destination.getId( ) );
            }
        }
        else
        {
            logger.warning( "Tried to add null destination to " + getId( ) );
        }
    }

    /**
     * Remove a single destination from this HighSeas instance.
     *
     * @param destination A destination <code>Location</code>.
     */
    public void removeDestination( Location destination )
    {
        destinations.remove( destination );
    }


    // Override FreeColGameObject

    /**
     * {@inheritDoc}
     */
    @Override
    public FreeColGameObject getLinkTarget( Player player )
    {
        return player.getEurope( );
    }

    // Interface Location (from UnitLocation)
    // Inherits
    //   FreeColObject.getId
    //   UnitLocation.getTile
    //   UnitLocation.getLocationLabelFor
    //   UnitLocation.add
    //   UnitLocation.remove
    //   UnitLocation.contains
    //   UnitLocation.canAdd
    //   UnitLocation.getUnitCount
    //   UnitLocation.getUnitList
    //   UnitLocation.getGoodsContainer
    //   UnitLocation.getSettlement

    /**
     * {@inheritDoc}
     */
    @Override
    public StringTemplate getLocationLabel( )
    {
        return StringTemplate.key( "model.tile.highSeas.name" );
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public Location up( )
    {
        return this;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public int getRank( )
    {
        return Location.LOCATION_RANK_HIGHSEAS;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String toShortString( )
    {
        return "HighSeas";
    }


    // UnitLocation
    // Inherits
    //   UnitLocation.getSpaceTaken
    //   UnitLocation.moveToFront
    //   UnitLocation.clearUnitList

    /**
     * {@inheritDoc}
     */
    @Override
    public NoAddReason getNoAddReason( Locatable locatable )
    {
        return ( locatable instanceof Unit && ( ( Unit ) locatable ).isNaval( ) )
                ? NoAddReason.NONE
                : NoAddReason.WRONG_TYPE;
    }


    // Serialization

    private static final String DESTINATION_TAG = "destination";


    /**
     * {@inheritDoc}
     */
    @Override
    protected void writeChildren( FreeColXMLWriter xw ) throws XMLStreamException
    {
        super.writeChildren( xw );

        for ( Location destination : destinations )
        {
            if ( destination == null ) continue;

            xw.writeStartElement( DESTINATION_TAG );

            xw.writeLocationAttribute( ID_ATTRIBUTE_TAG, destination );

            xw.writeEndElement( );
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected void readChildren( FreeColXMLReader xr ) throws XMLStreamException
    {
        // Clear containers.
        destinations.clear( );

        super.readChildren( xr );
    }

    /**
     * {@inheritDoc}
     */
    @Override
    protected void readChild( FreeColXMLReader xr ) throws XMLStreamException
    {
        final Game game = getGame( );
        final String tag = xr.getLocalName( );

        if ( DESTINATION_TAG.equals( tag ) )
        {
            addDestination( xr.getLocationAttribute( game, ID_ATTRIBUTE_TAG,
                                                     true ) );

            xr.closeTag( DESTINATION_TAG );

        }
        else
        {
            super.readChild( xr );
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String toString( )
    {
        return getId( );
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String getXMLTagName( ) { return getXMLElementTagName( ); }

    /**
     * Gets the tag name of the root element representing this object.
     *
     * @return "highSeas"
     */
    public static String getXMLElementTagName( )
    {
        return "highSeas";
    }
}
